StackOverflowException in linq query on json object

I am getting StackOverflowException when I try to run following linq query on following JSON object. It is observed that when the static function enclosing this query executed at the first time it runs well. But the next time it gives the error.

Exception message

An unhandled exception of type 'System.StackOverflowException' occurred in System.Core.dll

Here is the query

IEnumerable<long> iDs = = from p in jObject["response"]["docs"]
                              select Convert.ToInt64((string)p["id"]);

Here is the JSON object

{
  "responseHeader": {
    "status": 0,
    "QTime": 4,
    "params": {
      "sort": "noofsales desc, score desc",
      "fl": "id",
      "indent": "false",
      "start": "0",
      "q": "texttags:baby romper  bodysuit jumpsuit unisex boy girl animal costume sizes clothes deal offer\r\ndealtitle:baby romper  bodysuit jumpsuit unisex boy girl animal costume sizes clothes deal offer\r\nwhatyouget:baby romper  bodysuit jumpsuit unisex boy girl animal costume sizes clothes deal offer\r\nalltags:baby romper  bodysuit jumpsuit unisex boy girl animal costume sizes clothes deal offer\r\ndealdescription:baby romper  bodysuit jumpsuit unisex boy girl animal costume sizes clothes deal offer^80\r\ndealcity:National",
      "wt": "json",
      "fq": [
        "dealendtime:[NOW TO NOW+100YEAR]",
        "IF alltags: Experiences THEN dealcity:national National ELSE dealcity:national",
        "soldout:0"
      ],
      "rows": "24"
    }
  },
  "response": {
    "numFound": 35,
    "start": 0,
    "docs": [
      {
        "id": "787"
      },
      {
        "id": "23867"
      },
      {
        "id": "920"
      },
      {
        "id": "22768"
      },
      {
        "id": "1018"
      },
      {
        "id": "695"
      },
      {
        "id": "22890"
      },
      {
        "id": "23866"
      },
      {
        "id": "22741"
      },
      {
        "id": "1654"
      },
      {
        "id": "22975"
      },
      {
        "id": "23870"
      },
      {
        "id": "972"
      },
      {
        "id": "974"
      },
      {
        "id": "12379"
      },
      {
        "id": "12201"
      },
      {
        "id": "12199"
      },
      {
        "id": "1261"
      },
      {
        "id": "12205"
      },
      {
        "id": "12198"
      },
      {
        "id": "12191"
      },
      {
        "id": "12209"
      },
      {
        "id": "22919"
      },
      {
        "id": "12203"
      }
    ]
  }
}